Windows下Coqui TTS提示找不到eSpeak后端的排查求助

我在Windows系统下编写了Coqui TTS的测试脚本，已将eSpeakNG安装文件夹移至项目目录并配置了PATH相关环境变量。

测试脚本代码：

import os
import torch
from TTS.api import TTS
from TTS.utils.manage import ModelManager

# Get device
device = "cuda" if torch.cuda.is_available() else "cpu"

espeak_path = r"eSpeakNG"

# Add eSpeak to PATH
os.environ["PATH"] = espeak_path + os.pathsep + os.environ.get("PATH", "")
os.environ["ESPEAK_DATA_PATH"] = os.path.join(espeak_path, "espeak-ng-data")

# Show models
manager = ModelManager()
models = manager.list_models()
print(models)

# Initialize TTS-Model
tts = TTS(model_name="tts_models/de/thorsten/tacotron2-DDC")
# Save tts
tts.tts_to_file(text="Das ist ein Test.", file_path="output.wav")

运行脚本时始终收到如下错误：

File "C:\Python311\Lib\site-packages\TTS\tts\utils\text\phonemizers\espeak_wrapper.py", line 114, in __init__
raise Exception(" [!] No espeak backend found. Install espeak-ng or espeak to your system.")

Exception: [!] No espeak backend found. Install espeak-ng or espeak to your system.

我尝试运行以下代码验证eSpeakNG可用性：

import subprocess

espeak_path = r"eSpeakNG"
os.environ["PATH"] = espeak_path + os.pathsep + os.environ.get("PATH", "")
os.environ["ESPEAK_DATA_PATH"] = os.path.join(espeak_path, "espeak-ng-data")

try:
    result = subprocess.run(
        ["espeak-ng.exe", "--version"],
        capture_output=True,
        text=True,
    )
    print("eSpeak NG output:", result.stdout)
except FileNotFoundError:
    print("espeak-ng.exe not found.")

输出结果为：eSpeak NG output: eSpeak NG text-to-speech: 1.52-dev Data at: eSpeakNG\espeak-ng-data，说明eSpeakNG可正常调用。

同时通过以下代码验证动态链接库加载：

import ctypes

try:
    ctypes.CDLL(r"eSpeakNG\libespeak-ng.dll")
    print("libespeak-ng.dll successfully loaded.")
except OSError as e:
    print("Error loading libespeak-ng.dll:", e)

该代码也成功输出加载成功的信息。

请问是否还有Coqui TTS所需的配置项我遗漏添加到PATH中？

内容的提问来源于stack exchange，提问作者Joe